Use SDCC's new calling convention

(this is an ABI breaking change, and will require changes to
user-written asm functions or their declarations)

21 files changed, 88 insertions, 127 deletions

diff --git a/src/ubox/ubox_fill_screen.z80 b/src/ubox/ubox_fill_screen.z80
index e803f76..f07218c 100644
--- a/src/ubox/ubox_fill_screen.z80
+++ b/src/ubox/ubox_fill_screen.z80
@@ -4,8 +4,6 @@ FILVRM = 0x0056
 BG_TILE_MAP = 0x1800
 
 _ubox_fill_screen::
-	ld a, l
 	ld hl, #BG_TILE_MAP
 	ld bc, #768
 	jp FILVRM
-
diff --git a/src/ubox/ubox_get_tile.z80 b/src/ubox/ubox_get_tile.z80
index 3a6004d..9ea9b7b 100644
--- a/src/ubox/ubox_get_tile.z80
+++ b/src/ubox/ubox_get_tile.z80
@@ -4,13 +4,8 @@ RDVRM = 0x004a
 BG_TILE_MAP = 0x1800
 
 _ubox_get_tile::
-	ld hl, #2
-	add hl, sp
-
-	ld b, #0
-	ld c, (hl)
-	inc hl
-	ld l, (hl)
+	ld b, l
+	ld c, a
 
 	ld h, #0
 	add hl, hl
@@ -23,7 +18,4 @@ _ubox_get_tile::
 	ld bc, #BG_TILE_MAP
 	add hl, bc
 
-	call RDVRM
-	ld l, a
-	ret
-
+	jp RDVRM
diff --git a/src/ubox/ubox_get_vsync_freq.z80 b/src/ubox/ubox_get_vsync_freq.z80
index 681fe67..4a7f841 100644
--- a/src/ubox/ubox_get_vsync_freq.z80
+++ b/src/ubox/ubox_get_vsync_freq.z80
@@ -3,7 +3,6 @@
 _ubox_get_vsync_freq::
 	ld a, (#0x002b)
 	and #128
-	ld l, a
 	ret z
-	ld l, #1
+	ld a, #1
 	ret
diff --git a/src/ubox/ubox_isr.z80 b/src/ubox/ubox_isr.z80
index f25e35d..b8a19fe 100644
--- a/src/ubox/ubox_isr.z80
+++ b/src/ubox/ubox_isr.z80
@@ -12,7 +12,6 @@ REPCNT = 0xf3f7
 
 _ubox_init_isr::
 	di
-	ld a, l
 	ld (ubox_isr_wait_ticks), a
 	xor a
 	ld (ubox_isr_wait_tick), a
diff --git a/src/ubox/ubox_put_tile.z80 b/src/ubox/ubox_put_tile.z80
index 24e58b2..718027d 100644
--- a/src/ubox/ubox_put_tile.z80
+++ b/src/ubox/ubox_put_tile.z80
@@ -4,14 +4,11 @@ WRTVRM = 0x004d
 BG_TILE_MAP = 0x1800
 
 _ubox_put_tile::
+	ld c, a
+	ld b, l
+
 	ld hl, #2
 	add hl, sp
-
-	ld c, (hl)
-	inc hl
-	ld b, (hl)
-	inc hl
-
 	ld a, (hl)
 
 	ld h, #0
@@ -27,5 +24,8 @@ _ubox_put_tile::
 	ld bc, #BG_TILE_MAP
 	add hl, bc
 
-	jp WRTVRM
+	call WRTVRM
 
+	pop hl
+	inc sp
+	jp (hl)
diff --git a/src/ubox/ubox_read_ctl.z80 b/src/ubox/ubox_read_ctl.z80
index ae4fff9..d6f6a07 100644
--- a/src/ubox/ubox_read_ctl.z80
+++ b/src/ubox/ubox_read_ctl.z80
@@ -5,7 +5,6 @@ WRTPSG = 0x0093
 SNSMAT = 0x0141
 
 _ubox_read_ctl::
-	ld a, l
 	or a
 	jr z, is_keyb
 	dec a
@@ -13,7 +12,7 @@ _ubox_read_ctl::
 	dec a
 	jr z, is_joy2
 
-	ld l, #0
+	xor a
 	ret
 
 is_joy2:
@@ -49,7 +48,6 @@ call_psg:
 	xor a
 joy_extra_m:
 	or e
-	ld l, a
 	ret
 
 is_keyb:
@@ -96,5 +94,4 @@ is_keyb_dir:
 	or e
 	; added 2nd fire (M)
 
-	ld l, a
 	ret
diff --git a/src/ubox/ubox_read_keys.z80 b/src/ubox/ubox_read_keys.z80
index d32f2de..a8889fd 100644
--- a/src/ubox/ubox_read_keys.z80
+++ b/src/ubox/ubox_read_keys.z80
@@ -3,8 +3,6 @@
 SNSMAT = 0x0141
 
 _ubox_read_keys::
-	ld a, l
 	call SNSMAT
 	cpl
-	ld l, a
 	ret
diff --git a/src/ubox/ubox_read_vm.z80 b/src/ubox/ubox_read_vm.z80
index 7ef0f41..78df980 100644
--- a/src/ubox/ubox_read_vm.z80
+++ b/src/ubox/ubox_read_vm.z80
@@ -3,21 +3,23 @@
 LDIRMV = 0x0059
 
 _ubox_read_vm::
+	ex de, hl
+	; dst -> de
+	; len -> hl
+	ld c, l
+	ld b, h
+	; len -> bc
+
 	ld hl, #2
 	add hl, sp
-
-	ld e, (hl)
-	inc hl
-	ld d, (hl)
-	inc hl
-	ld c, (hl)
-	inc hl
-	ld b, (hl)
-	inc hl
 	ld a, (hl)
 	inc hl
 	ld h, (hl)
 	ld l, a
+	; src -> hl
 
-	jp LDIRMV
+	call LDIRMV
 
+	pop hl
+	pop bc
+	jp (hl)
diff --git a/src/ubox/ubox_select_ctl.z80 b/src/ubox/ubox_select_ctl.z80
index 9685bec..e313061 100644
--- a/src/ubox/ubox_select_ctl.z80
+++ b/src/ubox/ubox_select_ctl.z80
@@ -32,11 +32,11 @@ loop:
 	or a
 	jr nz, trigger_b
 
-	ld l, #0xff
+	ld a, #0xff
 	ret
 trigger_b:
 	dec b
 trigger:
 	dec b
-	ld l, b
+	ld a, b
 	ret
diff --git a/src/ubox/ubox_set_colors.z80 b/src/ubox/ubox_set_colors.z80
index 74a5b7f..4b89c99 100644
--- a/src/ubox/ubox_set_colors.z80
+++ b/src/ubox/ubox_set_colors.z80
@@ -6,17 +6,17 @@ BAKCLR = 0xf3ea
 BDRCLR = 0xf3eb
 
 _ubox_set_colors::
-	ld hl, #2
-	add hl, sp
-
-	ld a, (hl)
-	inc hl
 	ld (FORCLR), a
-	ld a, (hl)
-	inc hl
+	ld a, l
 	ld (BAKCLR), a
+
+	ld hl, #2
+	add hl, sp
 	ld a, (hl)
 	ld (BDRCLR), a
+
 	call CHGCLR
-	ret
 
+	pop hl
+	inc sp
+	jp (hl)
diff --git a/src/ubox/ubox_set_mode.z80 b/src/ubox/ubox_set_mode.z80
index 4635d34..373a145 100644
--- a/src/ubox/ubox_set_mode.z80
+++ b/src/ubox/ubox_set_mode.z80
@@ -3,6 +3,4 @@
 CHGMOD = 0x005f
 
 _ubox_set_mode::
-	ld a, l
 	jp CHGMOD
-
diff --git a/src/ubox/ubox_set_sprite_attr.z80 b/src/ubox/ubox_set_sprite_attr.z80
index 4e5c80e..ecf5952 100644
--- a/src/ubox/ubox_set_sprite_attr.z80
+++ b/src/ubox/ubox_set_sprite_attr.z80
@@ -4,14 +4,11 @@
 SP_ATTRS = 0x1b00
 
 _ubox_set_sprite_attr::
+	ld e, l
+	ld d, h
+
 	ld hl, #2
 	add hl, sp
-
-	ld e, (hl)
-	inc hl
-	ld d, (hl)
-	inc hl
-
 	ld l, (hl)
 	sla l
 	sla l
@@ -20,12 +17,11 @@ _ubox_set_sprite_attr::
 	add hl, bc
 
 	push de
-	ld bc, #4
-	push bc
-	push hl
+	ld de, #4
+	; hl: dst, de: len, stack: src
 	call _ubox_write_vm
-	pop af
-	pop af
-	pop af
-	ret
+
+	pop hl
+	inc sp
+	jp (hl)
 
diff --git a/src/ubox/ubox_set_sprite_pat16.z80 b/src/ubox/ubox_set_sprite_pat16.z80
index 59d7ccb..ee0f3c4 100644
--- a/src/ubox/ubox_set_sprite_pat16.z80
+++ b/src/ubox/ubox_set_sprite_pat16.z80
@@ -4,14 +4,11 @@
 SP_PATTERNS = 0x3800
 
 _ubox_set_sprite_pat16::
+	ld e, l
+	ld d, h
+
 	ld hl, #2
 	add hl, sp
-
-	ld e, (hl)
-	inc hl
-	ld d, (hl)
-	inc hl
-
 	ld l, (hl)
 	ld h, #0
 	add hl, hl
@@ -23,12 +20,10 @@ _ubox_set_sprite_pat16::
 	add hl, bc
 
 	push de
-	ld bc, #32
-	push bc
-	push hl
+	ld de, #32
+	; hl: dst, de: len, stack: src
 	call _ubox_write_vm
-	pop af
-	pop af
-	pop af
-	ret
 
+	pop hl
+	inc sp
+	jp (hl)
diff --git a/src/ubox/ubox_set_sprite_pat16_flip.z80 b/src/ubox/ubox_set_sprite_pat16_flip.z80
index 52f4ab7..7ac4077 100644
--- a/src/ubox/ubox_set_sprite_pat16_flip.z80
+++ b/src/ubox/ubox_set_sprite_pat16_flip.z80
@@ -4,14 +4,11 @@ WRTVRM = 0x004d
 SP_PATTERNS = 0x3800
 
 _ubox_set_sprite_pat16_flip::
+	ld e, l
+	ld d, h
+
 	ld hl, #2
 	add hl, sp
-
-	ld e, (hl)
-	inc hl
-	ld d, (hl)
-	inc hl
-
 	ld l, (hl)
 	ld h, #0
 	add hl, hl
@@ -32,7 +29,9 @@ _ubox_set_sprite_pat16_flip::
 	pop de
 	call flip
 
-	ret
+	pop hl
+	inc sp
+	jp (hl)
 
 flip:
 	ld b, #16
diff --git a/src/ubox/ubox_set_sprite_pat8.z80 b/src/ubox/ubox_set_sprite_pat8.z80
index 06b484c..c48588e 100644
--- a/src/ubox/ubox_set_sprite_pat8.z80
+++ b/src/ubox/ubox_set_sprite_pat8.z80
@@ -4,14 +4,11 @@
 SP_PATTERNS = 0x3800
 
 _ubox_set_sprite_pat8::
+	ld e, l
+	ld d, h
+
 	ld hl, #2
 	add hl, sp
-
-	ld e, (hl)
-	inc hl
-	ld d, (hl)
-	inc hl
-
 	ld l, (hl)
 	ld h, #0
 	add hl, hl
@@ -21,12 +18,10 @@ _ubox_set_sprite_pat8::
 	add hl, bc
 
 	push de
-	ld bc, #8
-	push bc
-	push hl
+	ld de, #8
+	; hl: dst, de: len, stack: src
 	call _ubox_write_vm
-	pop af
-	pop af
-	pop af
-	ret
 
+	pop hl
+	inc sp
+	jp (hl)
diff --git a/src/ubox/ubox_set_sprite_pat8_flip.z80 b/src/ubox/ubox_set_sprite_pat8_flip.z80
index b453253..64451e4 100644
--- a/src/ubox/ubox_set_sprite_pat8_flip.z80
+++ b/src/ubox/ubox_set_sprite_pat8_flip.z80
@@ -4,14 +4,11 @@ WRTVRM = 0x004d
 SP_PATTERNS = 0x3800
 
 _ubox_set_sprite_pat8_flip::
+	ld e, l
+	ld d, h
+
 	ld hl, #2
 	add hl, sp
-
-	ld e, (hl)
-	inc hl
-	ld d, (hl)
-	inc hl
-
 	ld l, (hl)
 	ld h, #0
 	add hl, hl
@@ -26,7 +23,10 @@ flip0:
 	inc hl
 	inc de
 	djnz flip0
-	ret
+
+	pop hl
+	inc sp
+	jp (hl)
 
 flip_and_copy:
 	ld a, (de)
diff --git a/src/ubox/ubox_set_tiles.z80 b/src/ubox/ubox_set_tiles.z80
index 7e4f42e..726eaae 100644
--- a/src/ubox/ubox_set_tiles.z80
+++ b/src/ubox/ubox_set_tiles.z80
@@ -19,4 +19,3 @@ _ubox_set_tiles::
 	ld de, #BG_TILES + #256 * 8 * 2
 	ld bc, #256 * 8
 	jp LDIRVM
-
diff --git a/src/ubox/ubox_set_tiles_colors.z80 b/src/ubox/ubox_set_tiles_colors.z80
index 4c4591b..6ca5d36 100644
--- a/src/ubox/ubox_set_tiles_colors.z80
+++ b/src/ubox/ubox_set_tiles_colors.z80
@@ -19,4 +19,3 @@ _ubox_set_tiles_colors::
 	ld de, #BG_COLS + 256  * 8 * 2
 	ld bc, #256 * 8
 	jp LDIRVM
-
diff --git a/src/ubox/ubox_wait_for.z80 b/src/ubox/ubox_wait_for.z80
index 5cc4649..f1984c8 100644
--- a/src/ubox/ubox_wait_for.z80
+++ b/src/ubox/ubox_wait_for.z80
@@ -4,11 +4,10 @@
 .globl ubox_isr_wait_tick
 
 _ubox_wait_for::
-	ld b, l
+	ld b, a
 wait_for_loop:
 	push bc
 	call _ubox_wait
 	pop bc
 	djnz wait_for_loop
 	ret
-
diff --git a/src/ubox/ubox_write_vm.z80 b/src/ubox/ubox_write_vm.z80
index 3d6606b..0daa7cc 100644
--- a/src/ubox/ubox_write_vm.z80
+++ b/src/ubox/ubox_write_vm.z80
@@ -3,21 +3,23 @@
 LDIRVM = 0x005c
 
 _ubox_write_vm::
+	ex de, hl
+	; dst -> de
+	; len -> hl
+	ld c, l
+	ld b, h
+	; len -> bc
+
 	ld hl, #2
 	add hl, sp
-
-	ld e, (hl)
-	inc hl
-	ld d, (hl)
-	inc hl
-	ld c, (hl)
-	inc hl
-	ld b, (hl)
-	inc hl
 	ld a, (hl)
 	inc hl
 	ld h, (hl)
 	ld l, a
+	; src -> hl
 
-	jp LDIRVM
+	call LDIRVM
 
+	pop hl
+	pop af
+	jp (hl)
diff --git a/src/ubox/ubox_wvdp.z80 b/src/ubox/ubox_wvdp.z80
index 90dfc86..b185f57 100644
--- a/src/ubox/ubox_wvdp.z80
+++ b/src/ubox/ubox_wvdp.z80
@@ -3,12 +3,6 @@
 WRITEVDP = 0x0047
 
 _ubox_wvdp::
-	ld hl, #2
-	add hl, sp
-
-	ld c, (hl)
-	inc hl
-	ld b, (hl)
-	call WRITEVDP
-	ret
-
+	ld c, a
+	ld b, l
+	jp WRITEVDP